An investigation into whether Florida State's star quarterback Jameis Winston sexually assaulted a woman is complete and will be announced on Thursday - just days before votes for the prestigious Heisman Trophy must be turned in.

Winston, 19, is the leading contending for the award as the country's best college football player.

The office of Florida State Attorney Willie Meggs said today that investigation has been concluded and the results of the probe will be announced at a news conference at 2 p.m. ET Thursday.

The announcement will complete a week of turmoil for the freshman star. On Monday, Meggs vowed that he would conduct a thorough investigation and that it would not be "based on a football schedule or anyone else's calendar."

On Tuesday, Winston was voted the Atlantic Coast Conference's rookie of the year. And on Saturday, the Florida State Seminoles, ranked No. 1 nationally, will play for the ACC title.

Winston has been hit with accusations of sexual battery in connection with an alleged assault in a Tallahassee apartment Dec. 7, 2012, according to a heavily redacted police report. However, the case did not reach prosecutors until last month.

Winston's attorney, Timothy Jansen, acknowledge his client had sex with his accuser, but insists it was consensual.

"We are hopeful that this cloud will be removed from Jameis as soon as possible," Jansen told ABC News Tuesday.

Jansen says he was told back in February by police that the case was closed. Interim Tallahassee Police Chief Tom Coe held a news conference two weeks ago and said the case was never closed.

"When we received a media inquiry, TPD consulted with the state attorney's office. At that time, that case was reopened or reactivated. Let me reiterate to you please, the case was never closed," Coe said.

The Tallahassee Police Department has come under fire for their handling of the investigation after the alleged victim's attorney said detectives warned them about pressing charges against Winston.

Detectives allegedly told the alleged victim's attorney, Patricia Carroll, that Tallahassee was a "big football town, and the victim needs to think long and hard before proceeding against him because she will be raked over the coals and her life will be made miserable," the victim's family said in a statement last month.

Coe said his department could only make "limited" remarks about the case because it was an open investigation and he did not want to influence the way the victim and Winston were treated.

But under mounting pressure, Tallahassee police finally took Winston's DNA samples last month, nearly a year after the alleged rape.

Meggs will ultimately decide whether charges should be brought against Winston, a freshman who has led FSU to an undefeated season. The timing of possible charges is coming at the height of Winston's monster season, passing for 3,490 yards and throwing 35 touchdowns.

ABC News' Gio Benitez and The Associated Press contributed to this report.